Apparatus for broad-drawing sheet materials

ABSTRACT

In a broad-drawing roll for moving webs of paper or the like, including a plurality of individual roll sections defining an arcuate curve to spread the web, the improvement which comprises a plurality of supporting bearings provided between the individual roll sections, said bearings being adjustable selectively and independently of one another and thereby determining the degree of curvature defined by said roll sections. Each roll section is mounted in freely rotatable fashion on its own shaft of substantially the same length as the section. Bearings, comprising two halves meeting along a line diametrically of the shaft, occupy substantially the full small space between adjacent roll sections.

United States Patent [191 Heymanns [451 Jan. 22, 1974 APPARATUS FOR BROAD-DRAWING SHEET MATERIALS [75] Inventor: Willia Heymanns, Hemmerden Ub.

Neuss, Germany [22] Filed: July 7, 1972 [21] Appl. No.: 269,695

[30] Foreign Application Priority Data Aug 5, 1971 Germany P 21 39 159.3

[52] US. Cl 226/194, 26/63, 29/125 [51] Int. Cl B65h 17/20 [58] Field of Search 226/190, 191, 192, 194;

[56] References Cited UNlTED STATES PATENTS 754,797 3/1904 Ostrander 26/63 3,648,342 3/1972 Dorfel 29/125 Primary Examiner-Richard A. Schacher Attorney, Agent, or Firm-Ralph D. Dinklage et al.

[5 7] ABSTRACT In a broad-drawing roll for moving webs of paper or the like, including a plurality of individual roll sections defining an arcuate curve to spread the web, the improvement which comprises a plurality of supporting bearings provided between the individual roll sections, said bearings being adjustable selectively and independently of one another and thereby determining the degree of curvature defined by said roll sections. Each roll section is mounted in freely rotatable fashion on its own shaft of substantially the same length as the section. Bearings, comprising two halves meeting along a line diametrically of the shaft, occupy substantially the full small space between adjacent roll sections.

5 Claims, 2 Drawing Figures PATENIED JAN 2 2 I974 SHEET 2 BF 2 APPARATUS FOR BROAD-DRAWING SHEET MATERIALS The invention relates to a broad-drawing roll for moving webs of paper, plastic or the like, which consists of a plurality of individual sections.

Broad-drawing rolls are used mostly where materials in web form, such as paper, foils, fabrics or the like, are being fabricated. They serve for the prevention of wrinkles in the webs such as might be caused by differences in tension in the plane of the web. These differences manifest themselves in the form of slack edges or sagging areas in the tensed web.

Broad-drawing rolls of the prior art consist generally of a flexible shaft on which a plurality of individual roller sections are mounted, these sections being covered by a rubber or plastic jacket extending over the entire length. The degree of curvature is selected and adjusted on the basis of the working width of the paper web and the quality of the paper. In these known rolls, the curvature runs symmetrically from the center of the roll towards the two shaft bearings. The disadvantage is that if the edge of the web is looser on one side than it is on the other, only one side of the web is stretched while the other side still tends to wrinkle. If the web edges are loose on oneside there is the danger of excessive straining of the area of the web that does not need equalization.

Attempts have therefore been made to use adjustable pressure battens whose curvature is variously adjustable and can be adapted to the particular requirements.

These pressure battens have the important disadvantage that, after only a brief period of operation, desposits collect to a greater or lesser extent depending on the kind of paper and surface coating, and these result in marks on the web.

The invention is addressed to the problem of eliminating the above-described disadvantages and creating a free-spinning broad-drawing roll which will be adjustable locally in any area of the paper web when slack edges or sagging areas occur.

This problem is solved in accordance with the invention by providing supporting bearings between the individual sections of the roll, these bearings being selectively adjustable independently of one another and determining the degree of curvature. The system at the same time is such that the individual roll sections are mounted so as to revolve freely independently of one another, each free-spinning section of the roll being mounted on a shaft corresponding substantially to the length of the section and the individual shafts being positively interengaged with one another. The supporting bearings may be disposed in the area of contact of two adjacent shafts bearing the roll sections, the width of the supporting bearing corresponding substantially to the interstice between the two roll sections.

In one especially advantageous feature of the invention the supporting bearings consist of two parts, the seam between these parts running crosswise of the center of the shaft and intersecting it.

The advantages achieved by the invention especially reside in that the broad-drawing roll is variable along any part of its curvature, so that slack web edges or sagging areas may be eliminated in certain circumscribed portions of the width of the paper web by varying the curvature of the broad-drawing roll only in this portion. A further advantage is that, owing to the easy replaceability of the roll sections, the stocking of bulky onepiece rolls is eliminated.

One embodiment of the invention is represented in the drawings wherein:

FIG. 1 is an overall view of the broad-drawing roll; FIG. 2 is a cross section taken along line 22 of FIG.

FIG. 3 is an enlarged view, partially in cross section, of a single roll section as taken along line 3-3 of FIG.

FIG. 4 is a cross section taken along line 44 of FIG. 3; and

FIG. 5 is a cross section taken along line 55 of FIG. 3.

Referring now more particularly to the drawings, as seen in FIG. 1, the broad-drawing roll 1 is arcuately disposed on a crossbeam 3 pivotally mounted by means of the shafts 2. It consists of individual roll sections 4 which are mounted in a freely rotatable manner on shafts 5. The individual roll sections 4 are mounted on the crossbeam 3 by means of divided supporting bearings 6 and adjusting bolts 7. The adjusting bolts 7 are each rotatably disposed in a bar'8 of the supporting bearing 6. The two supporting bearing halves 6to and 6" are joined together by the bar 9 and the screws 10.

For the replacement of individual roll sections 4, the bar 9 can be removed by unfastening the screws 10, and the bearing half 6" may thus be taken out. This makes the individual roll sections 4 easily replaceable without the expensive disassembly of all of the roll sections 4 or of the entire broad-drawing roll 1. The individual roll sections 4 are spaced apart only a small distance which is determined by the width of the supporting bearings 6. This assures a uniform, non-marking contact between the paper web 14 and the broaddrawing roll 1. In the area of the supporting bearings 6, the shafts 5 are constructed in such manner that each coupling portion 11 is positively engaged with the coupling portion of the adjacent shaft. The supporting bearing 6 is provided with recesses 12 for receiving the coupling portions 11.

The manner of operation of the broad-drawing roll is as follows. Starting from a paper roll processing machine, which is not shown, such as a rewinding machine or slitting machine in which broad-drawing rolls are required, the broad-drawing roll 1 is pivoted to the paper web 14 by means of a linkage 13 which engages the crossbeam 3. In this manner a general smoothing of the paper web takes place, such as is known in the broaddrawing rolls of the prior art. Upon the occurrence of web edges loose on one side or individual sagging areas in the outspread paper web, which cannot be eliminated by the prevailing curvature, the broad-drawing roll 1 is locally adjusted in the direction of the web. By loosening the nuts 15 it is possible by means of the adjusting screws 7 to force the supporting bearing 6 and hence the individual roll sections 4 against the paper web 14, thereby achieving an equalization of the loose web edges or of the sagging areas in the outspread paper web by a curvature change which is effective in this area only, while the curvature originally provided is maintained.

As shown in FIG. 2, the broad-drawing roll 1 is provided with a plurality of mechanically adjustable supporting bearings. It is also possible, however, for the purpose of achieving a more rapid adjustment of the supporting bearings, to equip the broad-drawing roll or supporting bearings with hydraulic or electrical means (not shown) so as to be able to automate the compensatory movements of the broad-drawing roll .in conjunction with an optical wrinkle detecting system (not shown).

It will be appreciated that the instant specification and examples are set forth by way of illustration and not limitation and that various modifications and changes may be made without departing from the spirit and scope of the present invention.

1 claim:

1. In a broad-drawing roll for moving webs of paper or the like, including a plurality of individual roll sections defining an arcuate curve to spread the web, the improvement which comprises a plurality of supporting bearings provided between the individual roll sections, said bearings being adjustable selectively and independently of one another and thereby determining the degree of curvature defined by said roll sections, and a shaft for each of said roll sections and each of substantially the same length as its respective roll section and having its roll section mounted freely rotatable thereon, the shafts being joined together in form-fitting manner.

2. A broad-drawing roll according to claim 1, wherein the individual roll sections are mounted in a freely rotatable manner independently of one another.

3. A broad-drawing roll according to claim 1, wherein the supporting bearings are disposed in the contact area of adjacent shafts bearing their respective roll sections.

4. A broad-drawing roll according to claim 3, wherein the width of the supporting bearings is substantially equal to the space between adjacent roll sections.

5. A broad-drawing roll according to claim 1, wherein each supporting bearing comprises two parts meeting along a separating seam running crosswise of the center of its shaft and intersecting it. 

1. In a broad-drawing roll for moving webs of paper or the like, including a plurality of individual roll sections defining an arcuate curve to spread the web, the improvement which comprises a plurality of supporting bearings provided between the individual roll sections, said bearings being adjustable selectively and independently of one another and thereby determining the degree of curvature defined by said roll sections, and a shaft for each of said roll sections and each of substantially the same length as its respective roll section and having its roll section mounted freely rotatable thereon, the shafts being joined together in form-fitting manner.
 2. A broad-drawing roll according to claim 1, wherein the individual roll sections are mounted in a freely rotatable manner independently of one another.
 3. A broad-drawing roll according to claim 1, wherein the supporting bearings are disposed in the contact area of adjacent shafts bearing their respective roll sections.
 4. A broad-drawing roll according to claim 3, wherein the width of the supporting bearings is substantially equal to the space between adjacent roll sections.
 5. A broad-drawing roll according to claim 1, wherein each supporting bearing comprises two parts meeting along a separating seam running crosswise of the center of its shaft and intersecting it. 